This invention relates to a light alloy body structure, particularly for transport vehicles such as buses, coaches and the like, and a process for its formation.
Aluminium buses and coaches, i.e. those provided with a load bearing or semi-load bearing aluminium body, have notably been constructed for some time. These buses and coaches offer numerous advantages over those constructed for example of steel. Their body is both very resistant to corrosion, therefore requiring minimum maintenance, and long-lasting, so allowing certain ammortization of the initial construction costs. Furthermore the aluminium body leads to a considerable lightening of the total weight of the vehicle structure, resulting either in greater loading or, for equal loads, greater engine efficiency and lower fuel consumption. The aluminium body has also proved to be particularly useful and effective in collisions, as it has greater facility for absorbing impact than similar structures of steel.
Up to the present time these bodies, or rather the structures forming the body framework, have been constructed integrally in a single block during assembly. Thus the base frame has been formed by joining together a series of suitably shaped sections, bars or laths during assembly, to gradually form the body shape. This shape is evidently three dimensional and very complicated, so that the construction of the body base frame has been particularly laborious and costly, due to the time required and the cost which this implied. Furthermore, such a process has had the disadvantage of requiring demanding repair work in the case of collision or structural damage, as nearly all the body elements are interdependent.